You have an open center hyd system, and you need a two spool valve to operate the loader.
A two spool valve has 4 work ports , each work port will feed a cyl port, A/B work ports will feed say the lift cyl's, and the C/D work ports will feed the cyl cyl. The work ports may be label 1,2,3,4, or A1,B1, A2, B2.
It will also have IN ,OUT, PB ports.
The standard loader valve is usually a joystick valve to operate the lift and the curl.
Here is a valve that will probably work if your loader does not have one.
Surplus Center - 2 SPOOL COMPACT 10 GPM JOYSTICK CONTROL VALVE
This valve has regen and float.
You need to find the pump pressure outlet from the tractor and feed the pressure line to the IN port of the loader valve and the valve PB outlet will feed the 3pt, and the OUT port of the valve will go to a tank line.